Built-in kitchens are increasingly being equipped with two ovens arranged one above the other in the form of a so-called dual oven in a shared housing in a kitchen cabinet, so that different baking and cooking processes can be carried out, especially at the same time. As a rule, such a dual oven has shared control, operating and display elements for both ovens in the top part of the housing. Usually, each oven has its own separate cooling-air system above the associated oven chamber so that sufficient cooling can be achieved. In order to be able to ensure the proper operation of both ovens, the electric systems, especially those located separately in the lower oven, are connected by means of electric connection lines to the central control and operating unit located in the top part of the housing. The drawback of such an oven construction is that, especially in the case of repair or maintenance work on the system or on components in the part of the housing above the lower oven, the built-in dual oven should be completely taken out of the kitchen cabinet and the shared housing has to be removed so that the upper oven can be lifted down from the lower oven in order for repair and maintenance work to be performed. Moreover, the connection lines between the two ovens arranged one above the other have to be disconnected for this purpose. It is also disadvantageous that, due to the size of such dual ovens, such repair and maintenance work normally has to be carried out by at least two people, resulting in higher labor costs, even for simple repair and maintenance work.